1. Field of the Invention
The present invention relates to a novel printing system for electronic apparatus provided with a printer, such as an electronic table calculator with printer (hereinafter such electronic apparatus is referred to simply as a printer machine).
2. Description of Prior Art
In the conventional printer machine, when the result of a calculation is printed for a key input on the key board, a symbol corresponding to the key input is printed together with data in one color, red or black, and on one line. Also, the conventional printer machine has some special keys which are used, for example, when data or a code number is printed. Non-address key ( # key) is an example of such special key. The printed symbol (#) corresponding to the key input of the non-address key is used to distinguish one item of calculation from other items or to represent the title.
However, this printing mode according to the prior art has some drawbacks. When the operator sees the printing paper printed in this printing mode after a series of calculations, it is difficult to understand at once what the printed output in a certain line means. The operator has to judge it from the print form (character printed at the most significant figure) or the printed symbol (#). It is never easy for the operator to quickly and correctly distinguish those printed data by the non-address key input from others at a glance. It renders the work in sorting the calculation items on the printing paper very troublesome and time-consuming.